Ignition apparatus



Jan. 6, 1948. AQ L BRowNLEE 2,433,887

I'Gumlon APPARATUS Filed Hay 5, 1946 f 6 Sheets-Sheet 1 INVENTOR M www@ n VM A'rroRNEYs Jan; 6, 1948. A, L, BRQWNLEE 2,433,887

IiGNITIoN APPARATUS Filed lay 3, 1946 e sheets-sheet 2 INVENToR AufmZMw/nff ATTGRNEYS Jan. 6, 1948. A. L BRowNLEE i 2,433,887

IGNITION APPARATUS Filed lay 3, 1946 6 Sheets-Sheet 3 4/ INVENTOR Aum/Lmwnr:

Jan. 6, 1948.

A. l. BRow'NLE:

IGNITION Arrmws Filed uw 3. 1946 6 shuts-Sheet 4 INVENTCR AunvL/mmuff ATTORNEYS Jan. 6, 1948,. A, 1 BROWNLEE 2,433,887

' IGNITION APPARATUS Filed May I5, 1946 6 Sheets-Sheet 5 32 ,l 2 f2 23 f a ,4

/s J 9 i l5 l l f5 ,l 60 a2 67 j a3 a6 12% *26g f; #--Jz M395 6 6 fl 94 5a l n .59 68 i' a 242/29 3/ 26' 524/ 32 l 4 Il l INVENTOR AufwLaw/mff ATTORNEYS d Jan. 6, 1948. A. L. BRowNLEE IGNITION APPARMUS Filed nays, 194e 6 Sheets-Sheet '6 INVENTOR Alf/vL/vamvzf:

9L ATTORN or substantially engage,

Patented Jan. 6, 1948 IGNITION APPARATUS Allen L. Brownlee, West Springfield, Mass., as-

signor,A to Wico Electric Company,

West Springfield, Mass., a. corporation of Massachusetts Application May s, 1946. serrer No. 666,921

whims. l

The invention relates ignition systems of the capacitor-discharge type, adapted for use with internal combustion engines, where it is desired to produce high-frequency sparks simultaneously at two spark plugs in each engine cylinder.

In a system of this kind, two capacitors are provided, one to serve one spark plug in each engine cylinder and the other to serve ,the other spark plug in each engine cylinder. Each capacitor is charged relatively gradually. That is. a relatively small current acts over an appreciable length of time to charge the capacitor. 'I'he discharge from the capacitor is, however, instantaneous and all the energy stored up in it over the charging interval is suddenly released. Hence, the discharge current will be relatively heavy even though of short duration. For example, the charging current may be only a few milliamperes while the discharge current may be 200 amperes. It is desirable to distribute the ignition current to both sets of yspark plugs by means of a single rotary member, lhaving two electrodes, which are connected one to each capacitor and which are adapted to successively move into confronting relation with and preferably to engage, with the xed electrodes of one series and the other with the fixed electrodes of another series. Such an arrangement necessitates at least three conductors, each having a pair of relatively-rotatable contacting elements. One pair of elements may be located at the axis of revolution of the rotatable distributor member but the other two pairs are necessarily radially spaced from the axis and are in the form of collector rings and brushes. Heretofore, the capacitors have been stationary and the discharge current has been transmitted through ail three pairs of elements. The result of such arrangement is that the heavy discharge current will burn the rings and form pits therein.. The

' rings become rough and then the brushes jump and fail to make good contact with the rings because they cannot follow into and out of the/'pits in the rings because of the high speed of relative movement. The initial trouble due to burning is thus rapidly made worse.

This invention has for one Object to overcome the diiiiculty described by mounting the capacitors on the rotatable distributor member and using the two rings and brushes solely for the purpose of conducting the charging current to the condensers. The central pair of contacting elements will be used as a common return for both condensers, both for the charging current to improvements in dual u and the discharge current. The central pair ci contacting elements, although carrying intermittently the heavy discharge currents, does not have the high speed of relative rotary movement that the rings and brushes do and the heavy dischargek current can be conducted through the centrally-located contacting elements without diiculty.

The invention has for another object to provide the distributor with one `rotary element upon which all the relatively heavy parts, such as capacitors and collecting rings are mounted, and with a second element, which carries only relatively light parts such as the movable distributor electrodes and may therefore be relatively light weight with low inertia. This second element is rotated by the rst element but it is also free to move in the direction of ther axis of rotation and to rock relatively to such axis for the purpose of enabling the movable electrodes to be adjusted into parallelism with each xed electrodeI which it confronts during its rotation. The second element, being free of the weight of the heavy parts, may readily move as necessary to enable adjustment of the positions of the movable electrodes.

The invention will be disclosed with reference to the acompanyi'ng drawings, in which; f

Fig. 1 is a sectional elevational view of an ignition apparatus embodying the invention;

Fig.2 is a .cross sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken on the line 3 3 of Fig. 2; l

Figs. 4 and 5 are cross sectional views taken on the lines 4-4 and 5 5, respectively. of Fig. 1;

Fig. 6 is a sectional view taken on the line 6-6 of F18. 5; l

Fig. 7 is a cross sectional view taken on the line 1-1 of Fig. 6; .l

Fig. 8 is a sectional view taken on the line 8-8 0f Fig. 5; /f l Fig. 9 is a diagram showing the /electrical connections of the ignition apparatus;

Fig. 10 is a view takensimilarly to Fig. 1 and f showing a modification;

Figs. 11 and 12 are sectional views taken on the lines il-II and lf2-I2, respectively, of Fig. 10; and

Fig. 13 is a fragmentary sectional view taken on the line II-II of Fig. 1

Referring to these drawings; the apparatus is housed in a cylindrical chamber l (Fig. 1) formed within a casing, having at its beck spider Maase? arms 2 (Fig. 2) and having a wall 3 together with a cover 4 (Fig. 1) the latter being suitably secured, as by screws 5, to wall 3. The casing 3 may have heat radiating fins 3' as shown. The drive shaft 6 has one of its bearings, as 1, supported by the spider armsI 2 and its free end extends into the chamber I. The casing described may be part of the casing of a generator, which supplies charging current for the capacitor, and the shaft B may be the drive shaft of such generator. Of course, the casing and shaft may also be independent of the generator with theshaft adapted to be connected to, and driven in timed relation with, the drive shaft of the generator.

Fixed to the arms 2, as by screws 8 (Figs. 2 and 3), is a member 9 of insulating material through the center of which shaft 6 freely passes. Member 9 contains two full-wave rectifiers, one on "each of two opposite sides of the shaft. Since the two rectifiers are alike in construction, one only will be described and corresponding parts of the other rectifier will be designated by the same ref" erence numerals with the addition of a prime. Each rectifier is of the selenium-cell, dry-disk type. One rectifier consists of four stacks of disks I6 (Fig. 2), two stacks being located in each of two parallel slots II in member 9 and held in place by a cover I2 of insulating material. Heat-radiating fins I3 also of electrical conducting material are interposed at intervals between the disks of each stack. Springs I4, (Fig. 2), one in each slot II press the disks together. The innermost disks of the two columns in each groove abut, and are electrically connected by a central terminal I6. The terminals I8 are the input terminals of the rectifier. The outer end disk of each column abuts and is electrically connected to a terminal I8. Each terminal I8 in one slot II is electrically connected to the adjacent terminal I8 in the other slot II. The connected terminals I8 are the output terminals of the rectifier. The member 9 (Figs. 1.

and 2) carries two spring-pressed brushes I9 and 26, one for each rectifier. Each brush is fixed in the outer end of a hollow plunger 2l (Fig. 1) slidably mounted in a guide piece 22, secured as by a screw 23 to member 9. These screws also serve to hold cover I2 to member 9. A spring 24 within the piece 22 and plunger 2l yieldingly urges its brush outwardly.

The drive shaft 8 (Fig. 1) has a shoulder 25 thereon, against which one face of a disk 26 of insulating material seats; a square portion 21, which passes centrally through the disk; and a threaded portion 28. This disk 26 carries on its other face two capacitors I and I1 which are shown only in diagrammatical form in Fig. 9.

These capacitors I5 and I1 are contained Within cylindrical cases 29 and 36 (Fig. 5), respectively, which are held to the disk by a strap 3I secured at its ends by screws 32 to the disk. The latter has curved seats (Fig. 1) therein, one for each of the cases 29 and 30 and the strap has parts curved to fit and partially encompass these cases. Each case forms one terminal of its capacitor. The other terminals of the two capacitors are shown at 33 and 34 (Figs. 5 and 8). The strap 3i extends diametrically of disk 26 (Fig. 5) and has a central opening through which the small portion 26 of the shaft passes (Fig. 1). A cap nut 35, threaded onto the shaft part 28, presses the central part of strap 3| against the disk and the latter against its seat 25 on the shaft 6. The strap and nut are thus firmly and electrically connected as they need to be in order to serve as parts of a common return conductor for both of the capacitors.

Suitably secured to the other face of member 25 are two annular collector rings 35 and 31 (Figs. 1 and 4) which are arranged one inside another and coaxially of shaft 6. The above described, spring-pressed brushes I9 and 2U ride on the rings 36 and 31 (Fig. 1), respectively. A pin 38 is fixed to member 26, as shown in Fig. 6 with one end in electrical contact with ring 36. Clamped to the member 26 by this pin is one end of a strap 39, the other end of which is connected to the insulated terminal 33 (Figs. 5, 6 and 8) of one capacitor. Another pin 48 (Fig. 6) is similarly fixed to member 26 and ring 31 and is connected by a metallic strap 4I (Figs. 5 and 8) to the terminal 34 of the other capacitor.

A distributor arm 42 (Figs. 1 and 6) is slidably mounted on the cylindrical exterior of nut 35, which serves as a supporting stud therefor. The arm 42 is pressed outwardly by a coil spring 43, which encompasses the stud. The pins 38 and 4II extend into and through openings in arm 42 (Fig. 6) and serve to cause it to rotate with its driving member 26. The nut 35 has near its outer end a flange 44 (Figs. 1 and 6) which limits the extent of axially outward movement of the arm by spring 43. The arm 42 has a loose enough fit with its supporting stud so that it is free to rock slightly if necessary into or out of a plane located at right angles to its axis of revolution. Fixed to this arm (Fig. 5), one on each side of its axis of revolution and at different radial distances from such axis, are two electrodes 45 and 46, one for capacitor I5 and the other for capacitor I1. These electrodes 45 and 46 engage with one end of springs 41 and 48, respectively, and are held to arm 42 by riveting. The other ends of springs 41 and 48 bear upon the outer ends of pins 38 and 40, respectively (Figs. 5, 6 and 8). Each electrode projects outwardly from arm 42 in a direction parallel to its axis of revolution.

A stationary disk 49 (Figs. i, 6 and 1) of insulating material is set into a counterbore in the outer end of chamber I (Fig. 1) and clamped in place'by the cover 4 described. A key 56 xed in wall 3 projects into a notch 5I in disk 49 and holds the latter against turning. This disk has an annular track 52, (Fig. '1) which may be of brass for example and which is located in a plane at right angles to the axis of revolution of arm 42.` The disk carries two series of fixed electrodes 53 and 54, disposed around said axis and facing toward arm 42 (Figs. 1 and 6) with their outer end faces adapted to be successively engaged by the outer end faces of the electrodes 45 and 46, respectively, on rotation of the arm 42. This arm has fixed thereto a plurality of brushes 55 (at least three, and as shown in Fig. 5, four) which ride on track 52 as indicated in Figs. 6 and 7 and thereby position arm 42 so that the outer end faces of its electrodes 45 and 46 are accurately located in the same transverse plane as that in which the outer end faces of the fixed contacts 53 and 54 are located. The electrodes 53 and 54 are inset into the disk 49 and their outer end faces lie in the plane of traclr` 52. Each electrode is set into the head of a rivet 56 (Fig. l) which passes through disk 49 and is headed over against a small leaf spring 51.

The cover carries a disk 58 (Figs. l and 6) of insulating material in which are mounted two circular series of terminal bolts 59 and 60. The bolts 59 and 6l) are angularly spaced to correaassr l i i spcnd with the angular spacing of electrodes I3 and 54, respectively. When thel covex` 4 is fastened in place, the springs 51, which are connected with the electrodes 53, engage the heads of the terminal bolts 59 and the springs, which are connected with the electrodes 54, engage the heads of the terminal bolts `6I). The disk 58 is seated against a shoulder 6I (Fig. 6) on the cover and held in position by a snap ring 62. In the center of disk 58 is a metal plug 63. Fixed to the outer face of plug 63 (Fig. 1) by means oi ascrew 64 is a spring 65 which presses against a wall of the metal cover 4 and serves as a ground connection. i

It will be seen that the outer` part of nut 35 passes freely through the disk 49 and Iterminates with its outer end face adjacent the plug 63 in disk 58. Slidable in and coaxially of nut 35 is a brush 66 which projects through and beyond said end face and rides on the inner end face of plug '63. A spring 61 within the nut presses the brush outwardly and a fiange 63 on the inner end of the brush serves by abutment with the inner face of the outer end wall oi the nut to limit the outward movement of the brush. The spring 65, screw 64, plug 63, brush 66, nut 35 and strap 3I form a common ground connection for both capacitors. l

The terminals 59 and 60 (Fig. 9) are adapted to be connected by distribution wires 69 and 19 to the primary windings 1I and 12 respectively, of spark-plug transformers, having secondary windings 13 and 14, respectively. One terminal of the primary of each transformer is connected to its secondary and grounded. The other terminals of the secondaries 13 and`14 are connected to spark plugs 15 and 16, respectively. There will be two spark plugs in each engine cylinder and the number of contacts in each circular series will equal the number of cylinders in the engine.

The input terminals I6 of one rectiiier are adapted to be connected, as by Wires 11 and 18, to a suitable source of alternating current, such as the coil or winding 19 of a suitable generator, such for example, as that shown, in the above identified application. The input terminals of the other rectifier are adapted to be connected as by wires 11"and 18 to another source of alternating current, such as the coil 19 of `another generator. The terminals I8 and I8 may be taken to represent the terminals of sources of charging current, in this case, rectiiid alternating current. One terminal I8 and one terminal I 8' of each rectier is connected to the metallic casing 3 and thereby grounded. The other terminal I8 of one rectifier is connected by brush I9, ring 36, pin 38,

minal 34 of the capacitor I1 is connected by strap 4I, pin 46, spring 48, electrode 46, an electrode V54. a terminal 60, a wire 19 to the primary 12iand thence through the grounded shielding to cover 4,

spring 66, plug 63, brush 66, nut 35, strap'3 to the case 30 of the capacitor I1.

Referring next to the form of the invention shown in Figs. 10, 11, 12 and 13, this is characterized by a different form of common return circuit for the two capacitors. Such circuit definitely excludes the rotor shaft and its bearing. The mounting of the rotor on its shaft is also diierent. Otherwise, the construction is like that heretofore shown and described and those parts in Figs. 10, 11, 12 and 13 which correspond exactly with parts in Figs. 1 to 9 inclusive have been designated by the same reference numerals. A rotor disk 26' (Fig. 10) has a central square hole to nt the squared portion 21 of the drive shaft 6 and a forwardly projecting hollow hub 89, A nut 8|, Within this hub, is threaded on. the portion 28 of the drive shaft and acts to clamp the disk 26' against the shoulder 25 on the shaft.

and conductor 39 to the terminal 33 0f capacitor I6 and thence by strap 3|, nut 35, brush 66 and spring' 65 to the cover 4 of the metallic casing 3. The other terminal I8 of the other rectier is connected by brush 29, ring 31, pin 46 and strap 4| to the terminal 34 of capacitor I1 and thence by strap 3i, nut 36, brush 66 and spring to the cover 4 of the metallic casing and thus to the ground. These are the charging circuits for the capacitors. The discharge circuits are aS set forth below. From terminal 33 of capacitor I5 by strap 39, pin 38. spring 41, electrode 45, an electrode 53, terminal 59, wire 69, primary 1I to the ground which in this case may be the metallic shielding in which wire 69 is carried and which is suitably connected to cover 4 and thus by spring 65, plug 63, brush 66, nut 35 and by strap 3| to the case 29 of capacitor I5. The ter- This disk carries on its rear face the collector rings 36 and 31, which are engaged by the brushes I9 and 29. On the front face of the disk are mounted the two capacitors, the cylindrical metal shells 29 and 39 of which are held in place by a strap 3i' secured at its ends by the screws 32. The central portion of this strap is U-shaped and extends along opposite flattened parts on the Deriphery of the hub 89 and across the outer end face of the latter. Fixed as by rivets 82, to this strap at its central portion, which crosses the outer end face of hub 80, is an Sshaped spring 83 (Fig. 11) bearing centrally .thereon a contact 84. The latter (see Fig. 10) is pressed by spring 83 against a carbon brush 85. fixed in the head of a bolt 86 which passes through disk 58 and is held thereto by a nut 81. The nut also serves to clamp to the disk 58 one end of the spring 65.

It will thus be seen that the connections from the shells 29 and 39 of the capacitors extend directly to cover 4. 'I'his strap 3| does not touch the shaft and therefore the shaftand its bearing are excluded from the return path to the rectifier. The latter is grounded by one of the screws 8 to one of the arms 2 of the housing. The ground path will thus be through cover 4, the Wall 3, an arm 2 and a screw 8, and all of these elements are closely held together. The other terminals of the capacitors I5 and I1 (Fig. 11) are wires 88 and 89 which have on their ends lugs 88 and 9|, secured by screws 92 and 93 to thin copper straps 94 and 95, respectively. The straps 94 and4 95 are respectively secured to collector rings 36 and 31 by rivets 96.

'I'he distributor arm 42 (Fig. 10) is slidably mounted on the hub and there is sufiicient clearance so that the arm can freely rock on the hub. The arm is driven from disk 26 by keys 91 (Figs. 11 and 12) which project from hub 89 at dlametrically opposite points near its outer end and enter keyways in the arm. As shown in Fig. 12, these keys are integral projections from a circular disk 98 which loosely fits in and closes the outer end of the bore of hub 80. The outer end face of hub 89 has grooves therein to receive these projections. The central portion of the strap 3l' overlies the disk 98 and thereby retains the projections in their grooves. The coil spring 43 (Fig. 19) surrounds hub 80 and acts to move arm 42' toward disk 49 and press the brushes 55 against track 52. As will be clear 7 from Fig. 12, the keys 91 will limit the outward movement of spring 43 and retain it in place on the hub 80 prior to assembly ofthe arm 42 thereon. When this arm is placed on the hub, the spring43 is compressed and does not engage the keys 91 under any normal condition of operation. The electrodes 45 and 46 are connected by flexible conductors 99 and |00 to the screws 92 and 93, respectively, and thus to the capacitors i and i1. These electrodes 45 and 46, as before, are adapted to successively engage fixed electrodes 53 and 54, respectively, arranged in circular series and mounted as heretofore described.

The electrical circuits for the second form of the invention are essentially the same as for the first form of the invention and differ only in the elements which make up certain conductors of the circuits. The elements 3|, 33, 34, 39 and 4|, shown in Fig. 9, are replaced by elements 3|', 92, 93, 94 and 95, respectively; the elements 38 and 4'| of Fig. 9 are replaced by element 99; the elements 4D and 48 are replaced by element |80; and the elements 66 and 63 of Fig. 9 are replaced by elements 83, 84, 85 and 86. It will be clear that these changes do not change the nature of the circuits in any way. However, the connection between the grounded terminal of each capacitor and the grounded terminal of the rectifier by way of elements 3|', 83, 84, 85, 86, 65, 4, 3, 2 and 8 definitely eliminates any possibility of current passing through the rotor shaft and its bearing and causing damage thereto and provides a path of excellent conducting quality.

While contact between each movable electrode and the fixed electrodes, which it successively confronts during rotation, is desirable and preferred in order to secure close accuracy in timing of the ignition sparks, there may be small gaps between the confronting electrodes and the arrangement of the floating distributor arm 42 or 42 with its brushes 55, track '52 and impelling spring 43 has the advantage of maintaining the faces of the electrodes as they come into confronting relation parallel and of maintaining all the gaps uniform and of compensating for wear as by erosion caused by sparking.

The operation is thesame for both forms of the invention. The capacitors i5 and l1 are charged during the intervals between `the engagement of successive fixed electrodes 53 and 64 by the rotatable electrodes 45 and 46, respectively. The charging occurs relatively gradually. A small charging current, which may be only a few milli-amperes, acts over a substantial time interval to build up the charge in each capacitor. The rectifiers prevent back flow of current so that the charges are retained in the capacitors until the rotating electrodes 45 and 46 respectively engage xed electrodes 53 and 64. Then, the capacitors are discharged. All the energy stored up in the capacitors is released suddenly and a substantially instantaneous discharge occurs, the discharge current being heavy, of the order of 200 amperes. The sudden discharge through the primaries and 72 produces a sudden and high tension current in the secondaries 13 and 14 and ignition sparks at the spark plugs 15 and 16, respectively. The operation has been but briefly summarized. The operation for each unit of the dual system is essentially the same as is disclosed in full detail in the copending application of Kenneth A. Harmon and Allen L. Brownlee, Serial No. 567,092, filed December 7, 1944, and assigned to the assignee of the present application.

This invention is characterized in that the capacitors are carried by a rotatable distributor member whereby the heavy discharge from the capacitors does not have to pass through the collector rings, such as 36 and 3l, as would be necessary if the capacitors were stationary as in the prior art. The heavy discharge current would form pits in the collector` rings and thus make the surfaces of the rings uneven so that the brushes could not make close contact with the ring, thereby promoting arcing between the brushes and rings and making the trouble worse. With the present arrangement, the collector rings carry only the capacitor-charging current which is extremely low and cannot cause pitting or damage to the rings. The brush 66 or 85 does carry the heavy discharge current but since it is located at the axis of rotation, the speed between the relatively-rotating surfaces is very small (zero at the center) and the brush 66 or 85 will maintain good electrical contact with members 63 or 84, respectively, notwithstanding the pitting. And there is, in addition, the follow up of the brush 66 or 85 to the member 63 or 84, respectively, whereby good contact is maintained. There is not the same trouble as exists where a collector ring, with pits in it, moves at high speed past a brush. Then, due to the inertia of the brush and the high relative rotary speed between it and the ring, the brush cannot follow the contour of the pits and ride into and out of them. The brushes then tend to jump and this aggravates the trouble. 4

The arrangement of the distributor in two rotatable parts allows the relatively heavier elements, such as the collector rings and capacitors and the retaining strap for the capacitors to be carried by one part such as 26 or 26', leaving only the relatively light elements, such as the electrodes 45 and 46 to be carried by the other, such as part 42 or 42. This enables the part 42 or 42', which has to float back and forth under pressure of spring 43, to be made very light and with low inertia so that it may readily be moved by the spring. The weight of the capacitors and collector rings is thus kept ofi the electrode-carrying distributor member 42 or 42',

which needs to be freely floating for the purpose described.

Irclaim:

1. In a dual ignition system, a rotatable distributor member, two capacitors carried by said member, a first and a second pair of relativelyrotatable charging-current-conducting elements one pair for each capacitor, each such pair including a. ring located coaxiaily with respect to the axis of rotation of said member and a brash riding on the ring, each rotatable element being carried by said member, a connection between each rotatable element and one terminal of its capacitor, the stationary elements adapted for connection one to one side of one source of charging current and the other to one side of another source of charging current, a third pair of contacting and relatively-rotatable elements located axially of' said member, the stationary elementr other side of both said sources, the rotatable element of the third pair being carried by said member and connected to the other terminal of both capacitors, a pair of electrodes carried by said member and located at different radial distances from said axis and connected one to the firstnamed terminal of one capacitor and the other to the first-named terminal of the other capacitor, and two series of stationary electrodes, one sel ries for each oi' the*first-named electrodes-the electrodes of eachk vsex'iesbeiugiradi'ally spaced so as to be successively engaged by vits nrst-lnamed electrode during rotationoi*saidmembergeach ystationary electrode yadapted lvfor connection 'tof` one terminal of the' primary winding of aspark plug transformer, the other terminal optvsaid winding adaptedy to be connectedl lto said stationary element of said third pail',r whereby'saidthirdfp'air of elements lcarry thedischarg'ecurrent''froniboth capacitors.

2. In a dual ignitionsystem.' arotatable driving memberof insulatingmaterial,` a pairpof capacitors carried on one face-oi." saidfmember, a pair of collector ringsfone for each' capacitor lcarried on the other face and coaxially foi' said niem-l ber, an electrical connection "betweenfwone' terminal of each capacitorrand its\ring`, a' pair'of brushes bearing one onone land thel other on the other oi' said rings and: adaptedv for' connection", one to one side oi'v a ksource of-chargingfcurrent and the other to 'one side of another source' of assegna? 3 the second member 'ate diderent radial distances fi'romf said axis, stationary electrodes Jadapted ro be successively engaged by oneofthe electrodes on said secondmemberfand other lstationary electrodesadapted to be'engaged' by the other electrode on said second member, said stationaryelec#4 ytrodes vadapted for; connectionl one to one terminaloi" theprlmary ofjeach of a plurality of spark plug transformersvv the other terminal oi.' each transformer primaryfadapted fory connection to said stationary element,'an electrical connection between' the'first-named terminaloi' each capacitor--fandvits movable electrodamean's for adjustably movingthe second member and for control-- ling such' movement `to position fthe `faces or the #movable electrodes as" they successively come into confronting relation with'the Afaces of their ilxed electrodes in'parallelism therewith, l

`4.`In\ a dual ignition system, a rotatable drivingmemberya pair oi' capacitors carriedfonlone vface ofsaid'member and equally spaced lfrom and on-oppositesidesof the axis of,y rotation thereof,

charging current, a pil-ir oirelativelyrotatablecontacting elements located' axiallyof 'saidlmember and the rotatable element oi'said p'airbeingfi carried by said member vand connectedy'toone terminal o! bothv capacitors, the stationary. eiement or said pair adapted for connection to the other side of both said sources, a' distributormemberxmounted on said driving member ,tobe roy tated thereby and for sliding movement in the direction of said axis, a pair oit, lectrodes' one for each capacitor carriedby sai isecondf'memberl at diii'erent radial distances from said'axis.

stationary electrodes adapted to be successively 1 engaged by one of the electrodes on'said second member and other stationary electrodes adapted to be engaged by the other electrode onfsaid'second member, said stationary electrodes adapted ior connection one to one terminal or the pri, mary oi' each of a pluralityv of spark plug trans-f i'ormers, the other terminal of :each vtransformer primary adapted for connection to `sa'ldst'ation ary element, an electrical connection between the first-named terminal of each capacitor and its'v movable electrode, means for -adiustably moving the second memberA and for controlling such movement to position the faces of the movable electrodes as they successively `come 'into coning current and the other to'one 'side of anotherk source oi.' charging current,v a third pair oticontacting and relatively-rotatable elements located axially of saidmember, the stationary 4element of the'third pair adapted to be connected tothe other side of both'said sources, therotatable element of the third pair being carried by's'aidlmemy ber and connected to the other terminal of both capacitors, a, relatively light member mounted on the driving member to' be rotated, thereby and for sliding movement of adjustment inthel general direction of said axis, lelectrodes 'carried' byrv 'I5l ai metallic 'strap serving as a clamp Afor both capacitorsand 'as partof a common return conductorfor the charging and discharging circuits thereof, said strap extending diametrically of said l member and having acentral contact. at distribu- I Vtormeinber rotatable with the driving member,

la pair of distributor electrodes carried by said distributor member and connected one to each `capacitor;' a stationary member having two series of electrodes one seriesfor each `'electrode on said'distributor member, a stationary contact located coaxially ofv said distributor member and connected to ground; a brush connection between f said contacts carried by one and riding on the v other: collector rings' on the other face of said vdriving/member yone for and connectedito each capacitor,l and stationary brushes one for and bearing on each ring for supplying charging current to the capacitors. l

' 5. In a dual ignltionsystem, a rotatable driving-member, a pair of'capacitors carried on one -face/ of said member and equally spaced from and on opposite sides of the axis of rotation thereof, a metallic strap serving as a clamp for both capacitorsand as 'part of a common return for the --charging and discharging circuits thereof, said strap extending diametrically of said member and havingy a `central contact portion, a distributor I member rotatable with said driving member, a

pair of distributor electrodes carried by said dis- `tributory member and connected one to each capacitor; a stationary member having two series of 'iixed electrodes, one series for each electrode on saidfdistributor member and having a track; said stationary `electrodes adapted for connection one 'to each of a` plurality oi' discharge circuits, said ooi distributor'm'e'mber being mounted on said drivingk memberfto move toward or away from said stationary member, spring means pressing said distributor member toward said stationary mem- "berfand a plurality of brushes carried by said distributor member and riding on said track to position the electrodes on the distributor member for engagement with the stationary electrodes *fvrith which it cooperates, a stationary' terminal located coaxially ofvsaid distributor member and forming a common return for the discharge circuits, a brush connection between said terminal and said contact portion,and carried by one and f ridingon the other, collector rings on the other face `of'said driving member one for and connected to each capacitor, andbrushes one for and 11 bearing on each ring for supplying charging current tc the capacitors.

6. In a dual ignition system, a rotatable driving member, a pair of capacitors carried on one face of said member and equally spaced from and on opposite sides of the axis of rotation thereof, a metallic strap serving as a clamp for both capacitors and as a common returnttor' the charging and discharging circuits thereof, and having centrally thereon a spring-pressed contact. said strap extending diametrically ot said member, a distributor member slidably mounted on said driving member, a pair of distributor electrodes carl 12 ber and riding on said track to position the movable electrodes properly with respect to the stationary electrodes with which it cooperates, a stationary terminal coaxial with said distributor member and adapted to be connected to all said discharge circuits, a brush on said terminal riding on said contact, collector rings on theother tace of said .driving member one for and connected to .v eachcapacitor, and brushesone for and riding on ried by said distributor member and 'connected one each ring for supply charging vcurrent to the capacitors.

Y AILEN L. nRowNLEE.

REFERENCES CITED The following references are oi.' record in the rile of this patent:

UNITED STATES PATENTS Number Name 4 Date 2,071,573 Randolph et al Feb. 23, 1937 2,349,437 Keeler May 23, 1944 2,373,247 Jones et a1 Apr. 10, 1945 

